Transmission

ABSTRACT

Power is transmitted by a planetary and hydraulic assembly which has one input shaft, two output means, and two reactions. While one output means is increasing its speed, the other output means is simultaneously decreasing its speed, and the ratio of the maximum speed of one output means to its minimum speed is substantially the same as the ratio of the maximum speed of the other output means to its minimum speed. This characteristic of speeding up one output means while the other slows down is used over and over again by shifting the final output from the point where one of the output means is going at maximum speed to the other output means when it is going at minimum speed, thus going through this cycle again and again. The power transmission therefore connects successively the final output drive to one output member of the planetary assembly and then to the other output member of the planetary assembly, and then back to the first output member of the planetary assembly at a different ratio from the previous connection, and so on, and this can be done because these output means continually increase and decrease their speeds.

United States Patent [72] Inventor Elias Orshansky, Jr. San Francisco, Calif. [21 Appl. No. 769,008 [22] Filed Oct. 21, 1968 [45] Patented May 25, 1971 [73] Assignee URS Systems Corporation San Mateo, Calif.

54 TRANSMISSION 93 Claims, 33 Drawing Figs.

[52] US. 74/687 [51 Int. Fl6h 47/08 [50] Field ofSearch 74/691,'

3,433,095 3/1969 Tuck ABSTRACT: Power is transmitted by a planetary and hydraulic assembly which has one input shaft, two output means, and two reactions. While one output means is increasing its speed, the other output means is simultaneously decreasing its speed, and the ratio of the maximum speed of one output means to its minimum speed is substantially the same as the ratio of the maximum speed of the other output means to its minimum speed. This characteristic of speeding up one output means while the other slows down is used over and over again by shifting the final output from the point where one of the output means is going at maximum speed to the other output means when it is going at minimum speed, thus going through this cycle again and again. The power transmission therefore connects successively the final output drive to one output member of the planetary assembly and then to the other output member of the planetary assembly, and then back to the first output member of the planetary assembly at a different ratio from the previous connection, and so on, and this can be done because these output means continually increase and decrease their speeds.

PATENTED W25 l97| SHEET 021 0F 27 III MI II III I I Inl INVENTOR. ELIAS ORSHANSKY, JR.

BY flan, ll/Maf AT TORNEYS PATENTED HAYES lsn SHEET 02 or 27 PATENTEDHAY25|97| 3,580.10?

SHEET u3ur27 INVENTOR.

dlu/Mw m ATTORNEYS ELIAS ORSH ANSKY, JR.

INVENTOR. ELIAS ORSHANSKYJR BY 0M,

ATTORNEYS SHEET 0% HF 27 PATENTED HAYZS IHYI PAIENTEU W25 19?: 3580,10?

sum as or 21 FIG. 7

ENTOR. ELIAS OR ANSKY,JR

ATTORN EYS PATENIED HAY25l97l 3580.107

SHEET 08 0F 27 FIG. 8

INVENTOR. ELIAS ORSHANSKY, JR

ATTORNEYS PATENTEU W25 l97| sum m or 27 FORWARD VENTOR. ELI AS O HANSKY,JR

AT TORNEYS PATENTED HAYZS IQYI SHEET as or 27 Ohm QNN/ MPN llllllllll lllllll mmm OWN

mON

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6m NON PATENTEI] HAYZSIBYI 3, 580, 1 O7 SHEET 10 0F 27 INVENTOR. ELIAS ORSHANSKYJR 0w. wM il-i ATTORNE Y S PATENTED HAY25 1971 3ZQBZO 318 SHEET 1101 27 I INVENTOR.

ELIAS ORSHANSKY,JR

0%,UMv8-L ATTORNEYS PATENTED MAY25 197i 3580.107

1 sum 13 or 27 Fl 6. 1 5 INVENTOR.

ELIAS ORSHANSKYJR 0M, wwkm ATTORNEYS SPEED OF PLANETARY MEMBERS PATENTEI] IIAY25 I97I I $580,107

saw 1 4 or 2 GEAR 4O GEAR 42 MESHED WITH MESHED WITH GEAR 44\ GEAR 46 SHIFT) SHIFT) SUN GEAR 22 RING GEAR 23- CARRIER 13 INPUT RING GEAR 21 SUN GEAR 24- OUTPUT SPEED OF SHAFT 50 FIG. 16

SPEED RELATIONSHIPS OF PLANETARY MEMBERS TO OUTPUT SHAFT OF FIG. 1

INVENTOR. EL IA 8 ORSHANSIC Y. JR.

0MwMwJA ATTORNEYS PATENTED HAY25 I97! SHEET 17 0F 27 E/Ew 5&50 m5 m0 (OOOL UF QDEIHDHOL DHOVHCIAH 

1. A power transmission comprising input means, output means, and a pair of gear trains for alternately connecting said input means with the output means, each train comprising a plurality of spaced transmission ranges of different ratios, each train including a planetary gear set with the planet gears of one set being intermeshed with the planet gears of the other set and a common carrier for both sets of planet gears driven by said input means, the ends of said ranges of each train overlapping the ends of the ranges of the other train between the maximum and minimum limits of transmission of the pair of trains, and means for alternately connecting and disconnecting the gear trains to the output means at said overlapping ends whereby power is transmitted alternately from said gear trains through the spaced transmissions to gradually drive the output means through the speed ranges.
 2. an input shaft driving said input means;
 2. an input shaft driving said input means;
 2. an input shaft driving said input means;
 2. an input shaft driving said input means;
 2. an input shaft driving said carrier;
 2. an input shaft driving said carrier;
 2. an input shaft driving said carrier;
 2. an input shaft driving said input means;
 2. an input shaft driving said input means;
 2. A power transmission comprising input means, output means, and a plurality of gear trains intermediately connected to each other by two intermeshed planet gear sets of a planetary gear arrangement and of overlapping speed ratios for connecting said input and output means, means for successively connecting each train to drive the output means through a preselected speed range, and means disconnecting each driving train from the output means after the following train has been connected thereto.
 2. an input shaft driving said carrier;
 2. an input shaft driving said carrier;
 2. an input shaft driving said carrier;
 2. transmitting torque from said rotary input member to said main output shaft through a first said rotary output member and a first said gear train;
 2. transmitting torque from said rotary input member to said main output shaft through a first said rotary output member and a first said outer gear train;
 2. transmitting torque from said rotary input member to said main output shaft through a first said rotary output member and a first said output gear train;
 2. an input shaft driving said carrier;
 3. a first hollow shaft mounting said first sun gear and concentric with said input shaft;
 3. operatively connecting said first pump-motor to said first reaction member and to said first member of said auxiliary planetary gear assembly to progress from zero speed and full stroke to maximum speed and zero stroke;
 3. causing said first pump-motor to be connected to a first said reaction member and to serve as a motor progressing from zero speed to maximum speed;
 3. causing a first said pump-motor connected to a first said reaction member to progress from zero speed and full stroke to maximum speed and zero stroke;
 3. a first hollow shaft mounting said first sun gear and concentric with said input shaft;
 3. a first hollow shaft mounting said first sun gear and concentric with said input shaft;
 3. a first sun gear shaft mounting said first sun gear;
 3. first and second output shafts mounting said pair of output means;
 3. a first sun gear shaft mounting said first sun gear;
 3. a first sun gear shaft mounting said first sun gear;
 3. a first sun gear shaft mounting said first sun gear;
 3. first and second output shafts mounting said pair of output means;
 3. first and second output shafts mounting said pair of output means;
 3. first and second output shafts mounting said pair of output means;
 3. first and second output shafts mounting said pair of output means;
 3. A power transmission comprising driving means, a planetary gear train connected to said means and having two sets of planet gears, one set being intermeshed with the other, a pair of output gears each in mesh with a different set of planet gears of said train, a pair of reaction gears each in mesh with a different set of said planet gears, and means interconnecting said reaction gears for regulating the reactive torque applied to said planet gears.
 3. first and second output shafts mounting said pair of output means;
 4. first and second reaction shafts mounting said pair of reaction means;
 4. first and second reaction shafts mounting said pair of reaction means;
 4. A device as defined in claim 3 further including driven means, a plurality of gear trains of different transmission ratios connected to said output gears, and means for alternately connecting the gear trains connected to one of the output gears and the gear trains connected to the other output gears to the driven means.
 4. first and second reaction shafts mounting said pair of reaction means;
 4. first and second reaction shafts mounting said pair of reaction means;
 4. first and second reaction shafts mounting said pair of reaction means;
 4. a second sun gear shaft mounting said second sun gear;
 4. a second sun gear shaft mounting said second sun gear;
 4. a second sun gear shaft mounting said second sun gear;
 4. first and second reaction shafts mounting said pair of reaction means;
 4. a second hollow shaft mounting said second sun gear and coaxial with and displaced linearly from said first hollow shaft;
 4. a second sun gear shaft mounting said second sun gear,
 4. a second hollow shaft mounting said second sun gear and coaxial with and displaced linearly from said first hollow shaft;
 4. a second hollow shaft mounting said second sun gear and coaxial with and displaced linearly from said first hollow shaft;
 4. simultaneously causing a second said pump-motor, connected to a second said rotary reaction member to retrogress from maximum speed and zero stroke to zero speed and full stroke;
 4. simultaneously causing said second pump-motor then serving as a pump, to move from zero stroke to full stroke;
 4. simultaneously causing said second pump-motor connected to said third reaction member to retrogress from maximum speed and zero stroke to zero speed and full stroke;
 5. whereby said first reaction member increases its speed and said first rotary output member increases its speed and the speed of the main output shaft, while said second reaction member decreases its speed and a second rotary output member decreases its speed;
 5. whereby said first rotary output member increases its speed and the speed of the main output shaft while a second rotary output member decreases its speed, and the speed of said first reaction member increases while the speed of said second reaction member decreases;
 5. whereby said first rotary output member increases its speed and the speed of the main output shaft while said second rotary output member decreases its speed;
 5. a third hollow shaft concentric with said first hollow shaft and mounting said first ring gear;
 5. a third hollow shaft concentric with said first hollow shaft and mounting said first ring gear;
 5. a first ring gear shaft mounting said first ring gear and having at least one output gear;
 5. a third hollow shaft concentric with said first hollow shaft and mounting said first ring gear;
 5. a first ring gear shaft mounting said first ring gear and having at least one output gear;
 5. a first ring gear shaft mounting said first ring gear and having at least one output gear;
 5. a first ring gear shaft mounting said first ring gear and having at least one output gear;
 5. at least one output gear on each said output shaft;
 5. at least one output gear on each said output shaft;
 5. at least one output gear on each said output shaft;
 5. at least one output gear on each said output shaft;
 5. A power transmission comprising an input shaft, an output shaft, and a pair of gear trains for alternately connecting said input shaft with the output shaft, each train comprising a plurality of spaced transmission ranges of different ratios, each train including a planetary gear set with the planet gears of one set intermeshed with the planet gears of the other set and a common carrier for both sets of planet gears driven by said input shaft, the ends of said ranges of each train overlapping the ends of the ranges of the other train between the maximum and minimum limits of transmission of the pair of trains, and means for alternately connecting and disconnecting the gear trains to the output shaft at said overlapping ends, whereby power is transmitted alternately from said gear trains through the spaced transmissions to gradually drive the output shaft through the speed ranges.
 5. at least one output gear on each said output shaft;
 5. at least one output gear on each said output shaft;
 6. a final output shaft having a plurality of driving gears each one driven by a said output gear to make a gear pair, said gear pairs providing different gear ratios between the input shaft and the final output shaft;
 6. a final output shaft having a plurality of driving gears each one driven by a said output gear to make a gear pair, said gear pairs providing different gear ratios between the input shaft and the final output shaft;
 6. A power transmission comprising an input shaft, an output shaft and a plurality of gear trains of overlapping speed ratios for connecting said shafts, each said gear train including a planetary gear arrangement with the planet gears of one train intermeshed with the planet gears of the other train, all of said planet gears being driven by said input shaft, means for successively connecting each train to drive the output shaft through a preselected speed range, and means disconnecting each driving train from the output shaft after the following train has been connected thereto.
 6. a final output shaft having a plurality of driving gears each one driven by a said output gear to make a gear pair, said gear pairs providing different gear ratios between the input shaft and the final output shaft;
 6. a final output shaft having a plurality of driving gears each one driven by a said output gear to make a gear pair, said gear pairs providing different gear ratios between the input shaft and the final output shaft;
 6. a final output shaft having a plurality of driving gears each one driven by a said output gear to make a gear pair, said gear pairs providing different gear ratios between the input shaft and the final output shaft;
 6. a final output shaft having a plurality of driving gears each one driven by a said output gear to make a gear pair, said gear pairs providing different gear ratios between the input shaft and the final output shaft;
 6. a second ring gear shaft mounting said second ring gear and having at least one output gear;
 6. a second ring gear shaft mounting said second ring gear and having at least one output gear;
 6. a second ring gear shaft mounting said second ring gear and having at least one output gear;
 6. a fourth hollow shaft concentric with said second hollow shaft and mounting said second ring gear;
 6. a second ring gear shaft mounting said second ring gear and having at least one output gear;
 6. a fourth hollow shaft concentric with said second hollow shaft and mounting said second ring gear;
 6. a fourth hollow shaft concentric with said second hollow shaft and mounting said second ring gear;
 6. shifting synchronously the drive to said main output shaft from said first gear train to a second gear train driven by said second rotary output member at an overlapping ration, the clutch means being caused to engage said second gear train to said main output shaft while said first gear train is still engaged therewith and then to disengage said first gear train therefrom;
 6. when said first and second reaction members attain the same speed, shifting synchronously the connection of said first pump-motor to said second reaction member and then disengaging it from said first reaction member, whereby said first pump-motor becomes a pump and second pump-motor becomes a motor;
 6. shifting synchronously the connection of said first pump-motor from to said first reaction gear train to said second reaction gear train;
 7. reversing the functional operation of said two pump-motors, so that the second pump-motor progress from zero speed and full stroke to maximum speed and zero stroke while the first pump-motor retrogresses from maximum speed and zero stroke to zero speed and full stroke, and so that said second reaction member increases its speed and said first rotary output member continues to increase its speed and further inCreases the speed of said main output shaft while the speeds of said first reaction member and said second rotary output member decrease;
 7. moving said second pump-motor from full stroke to zero stroke while moving said first pump-motor from maximum speed to zero speed, thereby further increasing the speed of said first rotary output member and further decreasing the speed of said second rotary output member, and also decreasing the speed of said second reaction member while further increasing the speed of said first reaction member;
 7. reversing the functional operation of said two pump-motors, so that the second pump-motor progresses from zero speed and full stroke to maximum speed and zero stroke while the first pump-motor retrogresses from maximum speed and zero stroke to zero speed and full stroke, and so that said second rotary output member increases its speed and further increases the speed of said main output shaft while the speed of said first rotary output member decreases;
 7. at least one output gear on said third hollow shaft;
 8. 8. at least one output gear on said fourth hollow shaft, having a different diameter from said one output gear on said third hollow shaft;
 7. at least one output gear on said third hollow shaft;
 7. an output shaft;
 7. at least one output gear on said third hollow shaft;
 8. at least one output gear on said fourth hollow shaft, having a different diameter from said one output gear on said third hollow shaft;
 7. an output shaft;
 7. an output shaft;
 7. an output shaft;
 7. means for separately causing each gear pair to transmit power to said final output shaft;
 7. means for separately causing each gear pair to transmit power to said final output shaft;
 7. means for separately causing each gear pair to transmit power to said final output shaft;
 7. means for separately causing each gear pair to transmit power to said final output shaft;
 7. A power transmission comprising an input shaft, an output shaft, and a plurality of gear trains for connecting said shafts, said plurality of gear trains including a pair of planetary gears having a common input driven by said input shaft and the planet gears of one being intermeshed with the planet gears of the other, means for connecting one of said trains to drive the output shaft through a first preselected speed range, means for connecting a second train to the output shaft during an end portion of said speed range, means for disconnecting said first train from the output shaft after the second train has been connected thereto, and means for driving the output shaft by said second train through a second preselected speed range after said first train has been disconnected.
 7. means for separately causing each gear pair to transmit power to said final output shaft;
 7. means for separately causing each gear pair to transmit power to said final output shaft;
 8. a pair of hydraulic units, each able to perform as a motor and, at a different time, as a pump, each mounted on a separate shaft for rotation therewith, with hydraulic conduit means connecting said pair of units;
 8. A power transmission comprising a driving shaft, a planetary gear train connected to said shaft, and having two sets of planet gears, one set being intermeshed with the other, a pair of output gears each in mesh with a different set of planet gears of said train, a pair of reaction gears each in mesh with a different set of said planet gears, and means interconnecting said reaction gears for regulating the reactive torque applied to said planet gears.
 8. a reversing gear on said final output shaft and an idling gear meshed therewith and to one said additional gear;
 8. a pair of hydraulic units, each able to perform as a motor and, at a different time, as a pump, each mounted on a separate shaft for rotation therewith, with hydraulic conduit means connecting said pair of units;
 8. a pair of hydraulic units, each able to perform as a motor and, at a different time, as a pump, each mounted on a separate shaft for rotation therewith, with hydraulic conduit means connecting said pair of units;
 8. a pair of hydraulic units, each able to perform as a motor and, at a diffErent time, as a pump, each mounted on a separate shaft for rotation therewith, with hydraulic conduit means connecting said pair of units;
 8. a plurality of driving gears on said output shaft, one driven by each said output gear, to make a plurality of gear pairs, either each said driving gear or each said output gear being secured to its shaft, the other of each said gear pair being freely rotatable upon its shaft;
 8. a plurality of driving gears on said output shaft, one driven by each said output gear, to make a plurality of gear pairs, either each said driving gear or each said output gear being secured to its shaft, the other of each said gear pair being freely rotatable upon its shaft;
 8. a plurality of driving gears on said output shaft, one driven by each said output gear, to make a plurality of gear pairs, either each sAid driving gear or each said output gear being secured to its shaft, the other of each said gear pair being freely rotatable upon its shaft;
 8. a starting gear on said final output shaft in driving relation with a mating gear on said first reaction shaft, to provide a starting gear pair;
 8. a plurality of driving gears on said output shaft, one driven by each said output gear, to make a plurality of gear pairs, either each said driving gear or each said output gear being secured to its shaft, the other of each said gear pair being freely rotatable upon its shaft;
 8. at least one output gear on said fourth hollow shaft, having a different diameter from said one output gear on said third hollow shaft;
 9. 9. an output shaft parallel to said hollow shAfts;
 8. shifting synchronously the drive to said main output shaft from said second gear traIn to a third gear train driven by said first rotary output member at a different overlapping ratio, engagement of said third gear train being followed by disengagement of said second gear train; and
 8. shifting synchronously the drive to said main output shaft from said first output gear train to a second output gear train driven by said second rotary output member at an overlapping ratio, the clutch means being caused to engage said second output gear train to said main output shaft while said first output gear train is still engaged therewith and then to disengage said first output gear train therefrom;
 8. shifting synchronously the drive to said main output shaft from said first output gear train to a second output gear train driven by said second rotary output member at an overlapping ratio, engagement of said second output gear train being followed by disengagement of said first output gear train; and
 9. again reversing the functional operation of said pump motors; and continuing to increase the speed of said main output shaft by shifting successively, first, between reaction gear trains and, second, between output gear trains of different overlapping ratios driven alternately by said rotary output members as set forth in steps (6) and (8) and by reversing the functional operation of said pump motors as set forth in steps (7) and (9).
 9. means for causing said starting and mating gears to transmit power from said first reaction shaft to said final output shaft;
 9. again reversing the functional operation of said two pump-motors, so that the first pump-motor again moves as a motor from zero speed to maximum speed, while the second pump-motor again moves as a pump from zero stroke to full stroke, and so that said second rotary output member increases its speed and further increases the speed of said main output shaft while the speed of said first rotary output member decreases and while the speed of said second reaction member increases while the speed of said first reaction member decreases; and
 9. again reversing the functional operation of said pump-motors; and continuing to increase the speed of said main output shaft by shifting successively between gear trains of different overlapping ratios driven alternately by said rotary output members as set forth in steps (6) and (8) and by reversing the functional operation of said pump-motors as set forth in steps (7) and (9).
 9. clutch means for clutching each said freely rotatable gear separately to its said shaft;
 9. an output shaft parallel to said hollow shafts;
 9. an output shaft parallel to said hollow shafts;
 9. clutch means for clutching each said freely rotatable gear separately to its said shaft;
 9. clutch means for clutching each said freely rotatable gear separately to its sAid shaft;
 9. clutch means for clutching each said freely rotatable gear separAtely to its said shaft;
 9. at least one additional gear mounted on each of said reaction shafts, for rotation therewith; and
 9. at least one additional gear mounted on each of said reaction shafts, for rotation therewith; and
 9. at least one additional gear mounted on each of said reaction shafts, for rotation therewith;
 9. means for causing said additional, idling and reversing gears to transmIt power to said output shaft;
 9. A device as defined in claim 8 further including a driven shaft, a plurality of gear trains of different transmission ratios connected to said output gears, and means for alternately connecting the gear trains connected to one of the output gears and the gear trains connected to the other output gear to the driven shaft.
 9. at least one additional gear mounted on each of said reaction shafts, for rotation therewith; and
 10. gear means on at least one of the shafts carrying a said hydraulic unit and driven by a said additional gear, whereby each said output gear is able to drive said final output shaft at a different input-speed-to-output-speed ratio and a shift can be made from an output gear on said first output shaft to an output gear on said second output shaft and vice versa at a time when one of said first and second output shafts is moving at its minimum speed and the other is moving at its maximum speed and when one said hydraulic unit is a pump and the other one is a motor and one is on Full stroke and the other is operating at zero stroke, so that the transmission can alternately transfer its output drive between said first and second output shafts in a recycling manner.
 10. A power transmission comprising a driving shaft, a pair of intermediate shafts, and an output shaft, a planetary gear train connected to said input shaft, and having two sets of planet gears, one set being intermeshed with the other, a pair of output gears, one carried by each of said pair of shafts, each in mesh with a different set of planet gears of said train, at least a pair of gear trains connected to each of said pair of shafts for selective connection to the output shaft, a pair of reactIon gears each in mesh with a different set of planet gears, and means connecting said reaction gears for regulating the reactive torque supplied by each reaction gear to the planet gears.
 10. a pair of hydraulic units, each able to perform as a motor and, at a different time, as a pump, each mounted on a separate shaft for rotation therewith, with hydraulic conduit means connecting said pair of units;
 10. gear means on at least one of the shafts carrying a said hydraulic unit and driven by a said additional gear, whereby each said output gear is able to drive said final output shaft at a different input-speed-to-output-speed ratio and a shift can be made from an output gear on said first output shaft to an output gear on said second output shaft and vice versa at a time when one of said first and second output shafts is moving at its minimum speed and the other is moving at its maximum speed and when one said hydraulic unit is a pump and the other one is a motor and one is on full stroke and the other is operating at zero stroke, so that the transmission can alternately transfer its output drive between said first and second output shafts in a recycling manner;
 10. gear means on at least one of the shafts carrying a said hydraulic unit and driven by a said additional gear, whereby each said output gear is able to drive said final output shaft at a different input-speed-to-output-speed ratio and a shift can be made from an output gear on said first output shaft to an output gear on said second output shaft and vice versa at a time when one of said first and second output shafts is moving at its minimum speed and the other is moving at its maximum speed and when one said hydraulic unit is a pump and the other one is a motor and one is on full stroke and the other is operating at zero stroke, so that the transmission can alternately transfer its output drive between said first and second output shafts in a recycling manner;
 10. gear means on at least one of the shafts carrying a said hydraulic unit and driven by a said additional gear, whereby each said output gear is able to drive said final output shaft at a different input-speed-to-output-speed ratio and a shift can be made from an output gear on said first output shaft to an output gear on said second output shaft and vice versa at a time when one of said first and second output shafts is moving at its minimum speed and the other is moving at its maximum speed and when one said hydraulic unit is a pump and the other one is a motor and one is on full stroke and the other is operating at zero stroke, so that the transmission can alternately transfer its output drive between said first and second output shafts in a recycling manner, said first said hydraulic unit being alternatingly coupled to the additional gear of said first reaction shaft through a first path comprising a first intermediate gear and a first gear on and clutchable to the shaft of said first unit and through a second path comprising said first intermediate gear, a shaft secured thereto, an input member of a torque-splitter planetary assembly also secured to said shaft, an output member of said torque-splitter planetary assembly, a second gear engaged with said output member, on and clutchable to the shaft of said first unit, and a reaction member of said torque-splitter planetary assembly connected to and rotating with the additional gear of the second reaction shaft.
 10. a pair of hydraulic units, each able to perform as a motor and, at a different time, as a pump, each mounted on a separate shaft for rotation therewith, with hydraulic conduit means connecting said pair of units;
 10. a pair of hydraulic units, each able to perform as a motor and, at a different time, as a pump, each mounted on a separate shaft for rotation therewith; with hydraulic conduit means connecting said pair of units;
 10. a pair of hydraulic units, each able to perform as a motor and, at a different time, as a pump, each mounted on a separate shaft for rotation therewith, with hydraulic conduit means connecting said pair of units;
 10. a plurality of gears freely rotatable on said output shaft, one driven by each said output gear;
 10. a plurality of gears freely rotatable on said output shaft, one driven by each said output gear;
 10. a pair of hydraulic units, each able to perform as a motor and, at a different time, as a pump, each mounted on a separate shaft for rotation therewith, with hydraulic conduit means connecting said pair of units;
 10. a plurality of gears freely rotatable on said output shaft, one driven by each said output gear;
 10. when said first and second reaction members once again attain the same speed, shifting synchronously the connection of said first pump-motor to said first reaction member and disengaging it from said second reaction member and then moving said second pump-motor from full stroke to zero stroke while it serves as a motor and while said first pump-motor, serving as a pump, moves from maximum speed to zero speed, thereby further increasing the speed of the output shaft, and continuing to increase the speed of said main output shaft by shifting successively between output gear trains of different overlapping ratios driven alternately by said rotary output members as set forth in step (8) and by intermediately shifting between said reaction gear trains as set forth in steps 6 and
 10. 10. a pair of hydraulic units, each able to perform as a motor and, at a different time, as a pump, each mounted on a separate shaft for rotation therewith, with hydraulic conduit means connecting said pair of units;
 11. clutch means on said output shaft for clutching each said gear separately to said output shaft;
 11. at least one additional gear mounted on each of said first and second sun gear shafts, for rotation with the sun gears thereof;
 11. clutch means on said output shaft for clutching each said gear separately to said output shaft;
 11. clutch means on said output shaft for clutching each said gear separately to said output shaft;
 11. at least one additional gear mounted on each of said first and second sun gear shafts, for rotation with the sun gears thereof; and
 11. at least one additional gear mounted on each of said first and second sun gear shafts, for rotation with the sun gears thereof;
 11. at least one additional gear mounted on each of said reaction shafts, for rotation therewith; and
 12. 12. gear means on at least one of the shafts carrying a said hydraulic unit and driven by a said additional gear, whereby each said output gear is able to drive said final output shaft at a different input-speed-to-output-speed ratio and a shift can be made from an output gear on said first output shaft to an output gear on said second output shaft and vice versa at a time when one of said first and second output shafts is moving at its minimum speed and the other is moving at its maximum speed and when one said hydraulic unit is a pump and the other one is a motor and one is on full stroke and the other is operating at zero stroke, so that the transmission can alternately transfer its output drive between said first and second output shafts in a recycling manner.
 11. at least one additional gear mounted on each of said first and second sun gear shafts, for rotation with the sun gears thereof; and
 11. a torque-splitting planetary assembly with first, second and third elements comprising the sun, planets and carrier, and ring gears, not necessarily in that order, said first element being drivingly connected to said first reaction shaft, said second element being drivingly connected to said second reaction shaft;
 11. means for retaining a fixed displacement on a first said hydraulic unit, two said gear means (10) being on the shaft of said hydraulic unit and separately clutchable thereto; one said gear means (10) being meshed with the additional gear on said first reaction shaft while the other is meshed with the additional gear on said second reaction shaft;
 11. at least one additional gear mounted on each of said reaction shafts, for rotation therewith; and
 11. A device as defined in claim 10 wherein the means for selectively connecting said gear trains comprises a clutch for connecting either one of said pair of gear trains to the output shaft, means for engaging said clutches for simultaneously driving the output shaft from a gear train connected to each of the intermediate shafts, and means for disengaging one of the clutches after the other clutch has been engaged.
 12. A device as defined in claim 11 wherein the means connecting said reaction gears comprises two fluid pump-motors, each able to serve as a pump at some times and as a motor at other times, means connecting said pump-motors together for driving the pump-motor which serves as a motor by the pump-motor which serves as a pump, a gear train connecting one of the reaction gears to one of the pump-motors, a gear train connecting the other of the reaction gears to the other pump-motor, and means regulating the output of the pump-motors.
 12. a pair of hydraulic units, each able to perform as a motor and, at a different time, as a pump, each mounted on a separate shaft for rotation therewith;
 12. gear means on at least one of the shafts carrying a said hydraulic unit and driven by a said additional gear, whereby each said output gear is able to drive said final output shaft at a different input-speed-to-output-speed ratio and a shift can be made from an output gear on said first output shaft to an output gear on said second output shaft and vice versa at a time when one of said first and second output shafts is moving at its minimum speed and the other is moving at its maximum speed and when one said hydraulic unit is a pump and the other one is a motor and one is on full stroke and the other is operating at zero stroke, so that the transmission can alternately transfer its output drive between said first and second output shafts in a recycling manner.
 12. means for varying the stroke of the second said hydraulic unit from full stroke in one direction through zero stroke to full stroke in the opposite direction;
 12. means for connecting and disconnecting said third element to the first of said pair of hydraulic units; and
 12. gear means on at least one of the shafts carrying a said hydraulic unit, driven by a said addition gear, whereby each said output gear is able to drive said output shaft at a different input-speed-to-output-speed ratio and a shift can be made from an output gear on said first ring gear shaft to an output gear on said second ring gear shaft and vice versa at a time when one of said ring gear shafts is moving at its minimum speed and the other is moving at its maximum speed and when one said hydraulic unit is a pump and the other one is a motor and one is on full stroke and the other is operating at zero stroke, so that the transmission can alternately transfer its output drive between said ring gear shafts in a recycling manner,
 12. gear means on each of the shafts carrying a said hydraulic unit, each driven by a different said addition gear, whereby each said output gear is able to drive said output shaft at a different input-speed-to-output-speed ratio and a shift can be made from an output gear on said first ring gear shaft to an output gear on said second ring gear shaft and vice versa at a time when one of said ring gear shafts is moving at its minimum speed and the other is moving at its maximum speed and when one said hydraulic unit is a pump and the other one is a motor and one is on full stroke and the other is operating at zero stroke, so that the transmission can alternately transfer its output drive between said ring gear shafts in a recycling manner.
 12. a pair of hydraulic units, each able to perform as a motor and, at a different time, as a pump, each mounted on a separate shaft for rotation therewith;
 12. gear means on at least one of the shafts carrying a said hyDraulic unit, driven by a said additional gear, whereby each said output gear is able to drive said output shaft at a different input-speed-to-output-speed ratio and a shift can be made from an output gear on said first ring gear shaft to an output gear on said second ring gear shaft and vice versa at a time when one of said ring gear shafts is moving at its minimum speed and the other is moving at its maximum speed and when one said hydraulic unit is a pump and the other one is a motor and one is on full stroke and the other is operating at zero stroke, so that the transmission can alternately transfer its output drive between said ring gear shafts in a recycling manner; and
 12. a pair of hydraulic units, each able to perform as a motor and, at a different time, as a pump, each mounted on a separate shaft for rotation therewith;
 12. gear means on at least one of the shafts carrying a said hydraulic unit, driven by a said additional gear, whereby each said output gear is able to drive said output shaft at a different input-speed-to-output-speed ratio and a shift can be made from an output gear on said first ring gear shaft to an output gear on said second ring gear shaft and vice versa at a time when one of said ring gear shafts is moving at its minimum speed and the other is moving at its maximum speed and when one said hydraulic unit is a pump and the other one is a motor and one is on full stroke and the other is operating at zero stroke, so that the transmission can alternately transfer its output drive between said ring gear shafts in a recycling manner;
 13. a torque-splitting planetary assembly with first, second and third elements comprising the sun, planets and carrier, and ring gears, not necessarily in that order, said first element being drivingly connected to said first sun gear shaft, said second element being drivingly connected to said second sun gear shaft;
 13. hydraulic conduit means connecting said pair of hydraulic units;
 13. said first said hydraulic unit being alternatingly coupled to the additional gear of said first sun gear shaft through a first path comprising a first intermediate gear and a first gear on and clutchable to the shaft of said first unit and through a second path comprising said first intermediate gear, an auxiliary shaft secured thereto, an input member of a torque-splitter planetary assembly also secured to said auxiliary shaft, an output member of said torque-splitter of said planetary assembly, a second gear engaged with said output member on and clutchable to the shaft of said first unit, and a reaction member of said torque-splitter planetary assembly connected to and rotating with the additional gear of said second sun gear shaft.
 13. hydraulic conduit means connecting said pair of hydraulic units;
 13. hydraulic conduit means connecting said pair of hydraulic units;
 13. means for retaining a fixed displacement on a first said hydraulic unit, two said gear means (12) being on the shaft of said first hydraulic unit and separately clutchable thereto, one said gear means (12) being meshed with the additional gear on said first sun gear shaft while the other is meshed with the additional gear on said second sun gear shaft;
 13. means for connecting and disconnecting at different times from each other each of said first and second elements to the second said hydraulic unit.
 13. a first coupling gear on the shaft of said second hydraulic unit; and
 13. A device as defined in claim 12 further including means for driving the output shaft in a reverse direction comprising a reversing gear train connected to one of the reaction gears and output shaft, clutch means for engaging said reversing train to and from the output shaft, and means for disengaging said pairs of gear trains from the output shaft before engaging said reversing train.
 14. A power transmission comprising: a driving shaft; a pair of intermediate shafts; an output shaft; a planetary gear train connected to said input shaft; an output gear carried by each of said pair of intermediate shafts in mesh with the planet gears of said train; at least a pair of gear trains connected to each of said pair of intermediate shafts; means for selectively connecting said gear trains to the output shaft, comprising a clutch for connecting either one of said pair of gear trains to the output shaft; means for engaging said clutches for simultaneously driving the output shaft from a gear train connected to each of the intermediate shafts; means for disengaging one of the clutches after the other clutch has been engaged; a pair of reaction gears in mesh with the planet gears; means connecting said reaction gears for regulating the reactive torque supplied by each reaction gear to the planet gears, comprising two fluid pump-motors, each able to serve as a pump at some times and as a motor at other times; means connecting said pump-motors together for driving the pump-motor when it serves as a motor by the other pump-motor when it serves as a pump; a first pair of gear trains for selectively connecting one of the reaction gears to the pump-motor serving as a pump; a second pair of gear trains for selectively connecting the other of the reaction gears to the pump-motor serving as a motor; means connecting one of said trains of the first pair to one of said trains of the second pair; and means for regulating the output of the pump-motors.
 14. a second coupling gear on Said input shaft meshed with said first coupling gear, to provide an input-coupled device.
 14. means for varying the stroke of the second said hydraulic unit from full stroke in one direction through zero stroke to full stroke in the opposite direction;
 14. at least one additional gear mounted on each of said first and second hollow shafts, for rotation with the sun gears thereof;
 14. at least one additional gear mounted on each of said first and second hollow shafts, for rotation with the sun gears thereof;
 14. at least one additional gear mounted on each of said first and second hollow shafts, for rotation with the sun gears thereof; and
 14. means for connecting and disconnecting said third element to the first of said pair of hydraulic units; and
 15. means for connecting and disconnecting at different times from each other each of said first and second elements to the second said hydraulic unit.
 15. two gear means, one on each of the said shafts that carry a said hydraulic unit and each driven by a different said additional gear, whereby each said output gear is able to drive said output shaft at a different input-speed-to-output-speed ratio and a shift can be made from an output gear on said third hollow shaft to an output gear on said fourth hollow shaft and vice versa at a time when one of said third and fourth shafts is moving at its minimum speed and the other is moving at its maximum speed and when one said hydraulic unit is a pump and the other one is a motor and one is on full stroke and the other is operating at zero stroke, so that the transmission can alternately transfer its output drive between said third and fourth hollow shafts in a recycling manner.
 15. two gear means, the gear means being on at least one of the said shafts that carry a said hydraulic unit and driven by a said additional gear, whereby each said output gear is able to drive said output shaft at a different input-speed-to-output-speed ratio and a shift can be made from an output gear on said third hollow shaft to an output gear on said fourth hollow shaft and vice versa at a time when one of said third and fourth shafts is moving at its minimum speed and the other is moving at its maximum speed and when one said hydraulic unit is a pump and the other one is a motor and one is on full stroke and the other is operating at zero stroke, so that the transmission can alternately transfer its output drive between said third and fourth hollow shafts in a recycling manner;
 15. two gear means, the gear means being on at least one of the said shafts that carry a said hydraulic unit and driven by a said additional gear, whereby each said output gear is able to drive said output shaft at a different input-speed-to-output-speed ratio and a shift can be made from an output gear on said third hollow shaft to an output gear on said fourth hollow and vice versa at a time when one of said third and fourth shafts is moving at its minimum speed and the other is moving at its maximum speed and when one said hydraulic unit is a pump and the other one is a motor and one is on full stroke and the other is operating at zero stroke, so that the transmission can alternately transfer its output drive between said third and fourth hollow shafts in a recycling manner;
 15. a first coupling gear on the shaft of said second hydraulic unit; and
 15. A device as defined in claim 11 wherein one of the gear trains of each of said pair includes an idler gear whereby each of said one of said gear trains can rotate the output shaft in a reverse direction.
 16. A power transmission comprising: a driving shaft; a pair of intermediate shafts, an output shaft; a planetary gear train connected to said input shaft; an output gear carried by each of said pair of intermediate shafts in mesh with the planet gears of said train; at least a pair of gear trains connected to each of said pair of shafts; means for selectively connecting said gear trains comprising a clutch for connecting either one of said pair of gear trains to the output shaft; means for engaging said clutches for simultaneously driving the output shaft from a gear tRain connected to each of the intermediate shafts; means for disengaging one of the clutches after the other clutch has been engaged; a pair of reaction gears in mesh with the planet gears; a first positive displacement hydraulic unit drivingly connected to the driving shaft; a second positive displacement hydraulic unit having a shaft; means connecting the two hydraulic units for driving one by the other; a gear train for connecting one of the reaction gears with the shaft of the second unit; a gear train for connecting the other reaction gear with the shaft of the second unit; clutch means for clutching said trains to the shaft of the second unit; and means regulating the output of the two hydraulic units.
 16. a second coupling gear on said input shaft meshed with said first coupling gear, to provide an input-coupled device.
 16. a torque-splitting planetary assembly with first, second and third elements comprising the sun, planets and carrier, and ring gears, not necessarily in that order, said first element being drivingly connected to said first hollow shaft, said second element being drivingly connected to second hollow shaft;
 16. means for retaining a fixed displacement on a first said hydraulic unit; and
 17. means for varying the stroke of a second said hydraulic unit from full stroke in one direction of flow through said conduit means through zero stroke to full stroke in the opposite direction of flow, said second hydraulic unit being coupled directly to the input shaft while both said gear means (15) are on the shaft for said first hydraulic unit and are separately clutchable thereto.
 17. means for connecting and disconnecting said third element to the first of said pair of hydraulic units; and
 17. A power transmission comprising a driving shaft, a pair of intermediate shafts, and an output shaft, a planetary gear train connected to said input shaft, a ring gear carried by each of said pair of shafts in mesh with the planet gears of said train, at least a pair of gear trains connected to each of said pair of shafts for selective connection to the output shaft, a pair of sun gears in mesh with the planet gears, and means connecting said sun gears for regulating the reactive torque supplied by each sun gear to the planet gears.
 18. A device as defined in claim 17 wherein the means for selectively connecting said gear trains comprises a clutch for connecting either one of said pair of gear trains to the output shaft, means for engaging said clutches for simultaneously driving the output shaft from a gear train connected to each of the intermediate shafts, and means for disengaging one of the clutches after the other clutch has been engaged.
 18. means for connecting and disconnecting at different times from each other each of said first and second elements to the second said hydraulic unit.
 19. A device as defined in claim 18 wherein the means connecting said sun gears comprises a fluid pump, a fluid motor, means connecting said pump and motor for driving the motor by the pump, a gear train connecting one of the sun gears to the pump, a gear train connecting the other of the sun gears to the motor, and means regulating the output of the pump and motor.
 20. A device as defined in claim 19 further including means for driving the output shaft in a reverse direction, comprising a reversing gear train connected to one of the sun gears and output shaft, clutch means for engaging said reversing train to and from the output shaft, and means for disengaging said pairs of gear trains from the output shaft before engaging said reversing train.
 21. A device as defined in claim 18 wherein the means connecting the sun gears comprises a fluid pump, a fluid motor, means connecting said pump and motor for driving the motor by the pump, a first pair of gear trains for selectively connecting one of the sun gears to the pump, a second pair of gear trains for selectively connecting the other of the sun gears to the motor, means connecting one of said trains of the first pair to one of said trains of the second pair, and means for regulating the output of the pump and motor.
 22. A device as defined in claim 18 wherein one of the gear trains of each of said pair includes an idler gear whereby each of said one of said gear trains can rotate the output shaft in a reverse direction.
 23. A power transmission comprising: a driving shaft; a pair of intermediate shafts; an output shaft; a planetary gear train connected to said input shaft; a ring gear carried by each of said pair of shafts in mesh with the planet gears of said train; at least a pair of gear trains connected to each of said pair of shafts; means for selectively connecting said gear trains, comprising a clutch for connecting either one of said pair of gear trains to the output shaft, means for engaging said clutches for simultaneously driving the output shaft from a gear train connected to each of the intermediate shafts, and means for disengaging one of the clutches after the other clutch has been engaged; a pair of sun gears in mesh with the planet gears; a first positive displacement hydraulic unit drivingly connected to the driving shaft; a second positive displacement hydraulic unit having a shaft; means connecting the two hydraulic units for driving one by the other; a gear train for connecting one of the sun gears with the shaft of the second unit; a gear train for connecting the other sun gear with the shaft of the second unit; clutch means for clutching said trains to the shaft of the second unit; and means regulating the output of the two hydraulic units.
 24. A power transmission for transmitting power between an input shaft and an output shaft, comprising: a plurality of fixed transmission ratio gear trains; a variable speed transmission driven by the input shaft including a pair of planetary gear assemblies each having a set of planet gears, one said set of planet gears being intermeshed with the other said set of planet gears and both sets having a common carrier and driven by said input shaft, each set being in engagement with output means of its said planetary gear assembly; means connecting the output means of said variable speed transmission to said gear trains to drive said trains; means for varying the speeds of said variable speed transmission to increase the speed of some of said trains and simultaneously reduce the speed of the remainder of said trains; the end portion of the speed range of the variable speed transmission producing the same transmission ratio between one of the trains of said some of said trains and one of the trains of said remainder of said trains; and means for simultaneously connecting one of the trains of said same transmission ratio to the output shaft and disconnecting the other of said trains of the same transmission ratio from the output shaft.
 25. The device of claim 24 wherein each planetary gear set of said variable speed transmission has a reaction member and the means for varying the speed of said variable speed transmission comprises a hydraulic motor connected to one of said reaction members, a pump connected to the other reaction member, and conduit means connecting the motor and pump.
 26. A recycling transmission, including in combination:
 27. The recycling transmission of claim 26 wherein there is a plurality of said output gears on each of said first and second output shafts, each making a gear pair with a said driving gear on said final output shaft.
 28. The recycling transmission of claim 27 wherein each said gear pair has a different ratio from that of the other gear pairs.
 29. The recycling transmission of claim 27 wherein said gear pairs come in twos on each said output shaft, one pair directly meshed for forward drive of said final output shaft and one pair connected to each other by an idler gear for reverse drive of said final output shaft.
 30. A recycling transmission, including in combination:
 31. A recycling transmission, including in combination:
 32. The recycling transmission of claim 26 having control means for operating said hydraulic means so that one of them is on full stroke while the other is operating at zero stroke and vice versa.
 33. The recycling transmission of claim 26 having separate control means for each said hydraulic means.
 34. A recycling transmission, including in combination:
 35. The recycling transmission of claim 26 having a single control means for all of said means for separately causing and for said hydraulic units.
 36. The recycling transmission of claim 35 wherein said single control means comprises a single shaft with a plurality of cam means thereon, separate valves operated by said cam means, separate hydraulic means for operating said means for separately causing and said hydraulic units, and a fluid pressure system controlled by said valves and controlling each of said hydraulic means.
 37. A recycling transmission, including in combination:
 38. A recycling transmission, including in combination:
 39. The recycling transmission of claim 37 wherein the second said hydraulic unit is connected to said second reaction shaft (a) by a first said additional gear on said second reaction shaft and a first gear on the shaft of said second unit and (b) as a second alternate path by a gear train comprising a second said additional gear on said second reaction shaft, a gear attached to and rotating with the reaction means of said torque-splitter planetary assembly, and a second gear on the shaft of said second unit, and wherein the second hydraulic unit is, as a third alternate connected by a third gear clutchable to its shaft and engaged with the first said gear on the shaft of said first unit.
 40. A recycling transmission, including in combination:
 41. The recycling transmission of claim 40 wherein there is a plurality of said output gears on each said ring gear shaft, each making a gear pair with a said driving gear on said output shaft.
 42. The recycling transmission of claim 41 wherein each said gear pair has a different ratio from that of the other gear pairs.
 43. The recycling transmission of claim 40 having a starting gear on said output shaft in driving relation with a mating gear on said first sun gear shaft, to provide a starting gear pair, one gear of which is in direct driving relation with its shaft while the other gear is freely rotatable on its shaft, and clutch means for clutching the freely rotatable gear to its said shaft.
 44. The recycling transmission of claim 40 wherein there is a reversing gear on said output shaft and an idling gear meshed therewith and to one said additional gear, and clutch means for clutching said reversing gear to said output shaft.
 45. The recycling transmission of claim 40 having control means for operating said hydraulic means so that one said hydraulic means is on full stroke while the other is operating at zero stroke and vice versa.
 46. The recycling transmission of claim 40 having separate control means for each said hydraulic means.
 47. A recycling transmission, including in combination:
 48. The recycling transmission of claim 47 wherein said gear pairs come in twos on the same ring gear shaft, one pair directly meshed for forward drive of said output shaft and one pair connected to each other by an idler gear for reverse drive of said output shaft.
 49. The recycling transmission of claim 40 having a single control means for all of said clutch means and for said hydraulic units.
 50. The recycling transmission of claim 51 wherein said single control means comprises a single shaft with a plurality of cam means thereon, separate valves operated by said cam means, separate hydraulic means for operating said clutch means and hydraulic units, and a fluid pressure system controlled by said valves and controlling each of said hydraulic means.
 51. A recycling transmission, including in combination:
 52. A recycling transmission, including in combination:
 53. The recycling transmission of claim 52 wherein said input member is a sun gear and said output member a planetary gear carrier unit having a toothed gear surface.
 54. The recycling transmission of claim 52 wherein the second said hydraulic unit is connected to said second sun gear shaft (a) by a first said additional gear on said second sun gear shaft and a first gear on the shaft of said second unit and (b) as a second alternate path by a gear train comprising a second said additional gear on said second sun gear shaft, a gear attached to and rotating with the reaction means of said torque-splitter planetary assembly, and a second gear on the shaft of said second unit, and wherein the second hydraulic unit is, as a third alternate, connected by a third gear clutchable to its shaft and engaged with the first said gear on the shaft of said first unit.
 55. The recycling transmission of claim 54 wherein said input member is a sun gear, said output member is a planetary gear carrier, and said reaction member is a ring gear.
 56. A recycling transmission, including in combination:
 57. The recycling transmission of claim 56 wherein there is a plurality of said output gears on each of said third and fourth hollow shafts, each being operatively connectable to a gear on said output shaft that is clutchable to said output shaft.
 58. The recycling transmission of claim 57 wherein each of the output gears and the gear operatively connectable thereto provides a different ratio from the others, to provide a different transmission ratio.
 59. The recycling transmission of claim 57 wherein some of said output gears mesh directly with their associated gears on said output shaft, to give a forward direction of rotation of said output shaft; and at least one of said output gears drives its associated gear on said output shaft through an idler gear to give a reverse direction of rotation of said output shaft.
 60. The recycling transmission of claim 56 wherein there is a starting gear on said output shaft meshed with the said additional gear on said first hollow shaft, and clutch means on said output shaft for clutching said starting gear to said output shaft.
 61. The recycling transmission of claim 56 wherein there is a reverse gear on said output shaft, clutch means for clutching said reverse gear to said output shaft, and idler gear means interposed between said reverse gear and the said additional gear on said first hollow shaft, for enabling that said additional gear to drive said reverse gear and to do so in a direction of rotation of the output shaft opposite to that in which said output gears drive it.
 62. The recycling transmission of claim 56 wherein there is control means for said pair of hydraulic units for first making one of them perform as a pump while the other performs as a motor and then making the other perform as a pump while the one performs as a motor, the one being on full stroke while the other is on zero stroke and vice versa.
 63. The recycling transmission of claim 56 wherein each said hydraulic unit has separate control means so that each one can separately be moved from full stroke to zero stroke and back.
 64. A recycling transmission, including in combination:
 65. The recycling transmission of claim 56 having single control means for controlling each of said clutch means and said hydraulic units.
 66. The recycling transmission of claim 65 wherein said single control means comprises a single shaft, a set of cams mounted thereon, a cam follower engaging each said cam, valve means operated by each of said cam followers, hydraulic means for operating each said clutch means and a fluid pressure system controlled by said valve means for actuating each said hydraulic means.
 67. The recycling transmission of claim 66 wherein said shaft also carries a cam for operating one said hydraulic unit through a cam follower, valve, said fluid pressure system and a hydraulic means.
 68. The recycling transmission of claim 67 wherein said one said hydraulic unit has means for operating the other said hydraulic unit in a reverse mode, so that when one is on full stroke the other is on zero stroke and vice versa.
 69. The recycling transmission of claim 68 wherein only said one said hydraulic unit is so controlled, the other said hydraulic unit operating at a fiXed stroke.
 70. The recycling transmission of claim 67 wherein each said hydraulic unit has its own said cam, cam follower, valve, and hydraulic means.
 71. A recycling transmission, including in combination:
 72. The recycling transmission of claim 58 wherein said gear means (15) of a first of said pair of hydraulic units has clutch means for clutching and declutching it from the shaft for said first hydraulic unit.
 73. The recycling transmission of claim 72 wherein said gear means (15) of said first hydrauLic unit is driven through first and second intermediate gears by the said additional gear on said first hollow shaft.
 74. The recycling transmission of claim 73 wherein said first intermediate gear drives a sun gear of a splitter planetary assembly having a carrier with an external gear comprising said second intermediate gear.
 75. The recycling transmission of claim 74 wherein said shaft of said first hydraulic unit has two gears thereon, each separately clutchable to that said shaft, a first one being driven by said first intermediate gear through said planetary carrier and a second gear being driven from said first intermediate gear by a directly meshed other intermediate gear.
 76. The recycling transmission of claim 75 wherein the second of said hydraulic units has a shaft with three gears mounted thereon, each separately clutchable to that said shaft, a first of these said three gears being directly meshed with the said second gear on the shaft of the first hydraulic unit, a second said gear of said three gears being driven directly by a said additional gear on said second hollow shaft, and a third said gear of said three gears driven from a further additional said gear on said second hollow shaft through a special intermediate gear.
 77. The recycling transmission of claim 76 wherein said special intermediate gear is connected directly by a shaft to a ring gear of said splitter planetary assembly.
 78. A device as defined in claim 16 wherein one of the gear trains of at least one said pair includes an idler gear, whereby said one of said gear trains can rotate the output shaft in a reverse direction.
 79. A device as defined in claim 23 wherein one of the gear trains of at least one of said pair includes an idler gear whereby said one of said gear trains can rotate the output shaft in a reverse direction.
 80. The recycling transmission of claim 47 wherein there is a plurality of said output gears on each said ring gear shaft, each making a gear pair with a said driving gear on said output shaft.
 81. The recycling transmission of claim 47 wherein each said gear pair has a different ratio from that of the other gear pairs.
 82. The recycling transmission of claim 47 having control means for operating said hydraulic means so that one said hydraulic means is on full stroke while the other is operating at zero stroke and vice versa.
 83. The recycling transmission of claim 64 wherein there is a plurality of said output gears on each of said third and fourth hollow shafts, each being operatively connectable to a gear on said output shaft that is clutchable to said output shaft.
 84. The recycling transmission of claim 64 wherein each of the output gears and the gear operatively connectable thereto provides a different ratio from the others, to provide a different transmission ratio.
 85. The recycling transmission of claim 64 wherein some of said output gears mesh directly with their associated gears on said output shaft, to give a forward direction of rotation of said output shaft; and others of said output gears drive their associated gear on said output shaft through an idler gear to give a reverse direction of rotation of said output shaft.
 86. A power transmission comprising: a driving shaft; a pair of intermediate shafts; an output shaft; a planetary gear train connected to said input shaft; an output gear carried by each of said pair of intermediate shafts in mesh with the planet gears of said train; at least a pair of gear trains connected to each of said pair of shafts; means for selectively connecting said gear trains comprising a clutch for connecting either one of said pair of gear trains to the output shaft; means for engaging said clutches for simultaneously driving the output shaft from a gear train connected to each of the intermediate shafts; means for disengaging one of the clutches after the other clutch has been engaged; a reaction gear in mesh with the planet geArs of one said train; a first positive displacement hydraulic unit drivingly connected to the driving shaft; a second positive displacement hydraulic unit having a shaft; means connecting the two hydraulic units for driving one by the other; a gear train for connecting said reaction gear with the shaft of the second unit; and means regulating the output of the two hydraulic units.
 87. A power transmission comprising: a driving shaft; a pair of intermediate shafts; an output shaft; a planetary gear train connected to said input shaft; a ring gear carried by each of said pair of shafts in mesh with the planet gears of said train; at least a pair of gear trains connected to each of said pair of shafts; means for selectively connecting said gear trains, comprising a clutch for connecting either one of said pair of gear trains to the output shaft, means for engaging said clutches for simultaneously driving the output shaft from a gear train connected to each of the intermediate shafts, and means for disengaging one of the clutches after the other clutch has been engaged; sun gear means in mesh with the planet gears; a first positive displacement hydraulic unit drivingly connected to the driving shaft; a second positive displacement hydraulic unit having a shaft; means connecting the two hydraulic units for driving one by the other; a gear train for connecting said sun gear means with the shaft of the second unit; and means regulating the output of the two hydraulic units.
 88. A method of operating a transmission of the type having a planetary gear assembly with a rotary input member, a pair of rotary reaction members, and a pair of rotary output members, said transmission also having a pair of fluid pump-motors hydraulically connected together, each able to serve as a pump at some times and as a motor at other times, one serving as a pump when the other serves as a motor and vice versa, and each being connected to a said rotary reaction member, and a series of gear trains of overlapping ratios, a plurality for each said rotary output member, a main output shaft, and clutch means for connecting said main output shaft to each said rotary output member through a said gear train, comprising the steps of:
 89. The method of claim 88 characterized by a constant ratio between the maximum and minimum speeds of said main output shaft for every one of said gear trains.
 90. A method of operating a transmission of the type having a planetary gear assembly with a rotary input member, a pair of rotary reaction members, and a pair of rotary output members, said transmission also having first and second fluid pump-motors hydraulically connected together, each able to serve as a pump at some times and as a motor at other times, one serving as a pump while the other serves as a motor and vice versa, said first pump-motor being kept at constant stroke and being connectable in alternation through first and second reaction gear trains to each of said rotary reaction members, said second pump-motor always being connected operatively to said rotary input member, and a series of output gear trains of overlapping ratios, a plurality for each said rotary output member, a main output shaft, and clutch means for connecting said main output shaft to each said rotary output member through a said gear train, comprising the steps of:
 91. The method of claim 90 characterized by a constant ratio between the maximum and minimum speeds of said main output shaft for every one of said output gear trains.
 92. A method of operating a transmission of the type having a main planetary gear assembly with a rotary input member, first and second rotary reaction members, and a pair of rotary output members, said transmission also having an auxiliary planetary gear assembly with a first member connected to said first reaction member, a second member connected to said second reaction member, and a third reaction member, each of said first and second members acting sometimes as an input while the other acts as an output and vice versa, said transmission having first and second fluid pump-motors, hydraulically connected together, each able to serve as a pump at some times and as a motor at other times, one serving as a pump while the other serves as a motor and vice versa, said first pump-motor being connectable in alternation through first and second reaction gear trains to each of said rotary reaction members, said first pump-motor at the same time being connected to one of said first and second members of said auxiliary planetary gear assembly, said second pump-motor being connected to the third reaction member, and a series of output gear trains of overlapping ratios, a plurality for each said rotary output member, a main output shaft, and clutch means for connecting said main output shaft to each said rotary output member through a said output gear train, comprising the steps of:
 93. The method of claim 92 characterized by a constant ratio between the maximum and minimum speeds of said main output shaft for every one of said output gear trains. 